Licks 27a and 27b provide two variations to the train rhythms described in Progressive Blues Harmonica. Note that 27b utilizes entirely inhaled notes, and thus cannot be maintained indefinitely without running out of breath.
It also employs a moderate "swing" beat, emphasizing the first of any two notes that occupy a single beat, as indicated by the " . " notation symbol.
Lick 27c alternates the use of licks 27a and 27b, in the form: 27a – 27b – 27a – 27b – 27a – 27b. Alternating these two train variations allows them to be played continuously, since 27a, unlike 27b, uses exhaled notes as well as inhaled.
Lick 27d is similar to Lick 27a, but sometimes (in every other line, in the notation below) breaks the first beat of 123i chord into two parts. This creates a more interesting rhythmic pattern than the use of 27a alone.
Lick 27e is a version of Lick 27a which leaves the last note of each two bars silent. This silent beat allows ample time to go to a whistle.